Aluminum base alloy electrical conductor

ABSTRACT

Aluminum alloy electrical conductors are produced from aluminum base alloys containing from about 0.55 percent to about 0.95 percent by weight cobalt, optionally up to about 2.0 percent of additional alloying elements, and from about 97.45 percent to about 99.45 percent by weight aluminum. The alloy conductors have an electrical conductivity of at least 57 percent, based on the International Annealed Copper Standard (IACS), and improved properties of increased thermal stability, tensile strength, percent ultimate elongation, ductility, fatigue resistance and yield strength as compared to conventional aluminum alloys of similar electrical properties.

United States Patent [191 Schoerner et' al.

[ 1 ALUMINUM BASE ALLOY ELECTRICAL CONDUCTOR [75] Inventors: Roger J. Schoerner; Enrique C.

Chia, both of Carrollton, Ga.

[73] Assignee: Southwire Company, Carrollton,

22 Filed: Dec. 1, 1970 21 Appl. No.: 94,192

Related US. Application Data [63] Continuation-in-part of Ser. No. 54,563, July 13,

1970, abandoned.

[52] US. Cl 29/193, 29/527.7, 75/138, 148/2, 148/115 A, 148/32, 164/76 [51] Int. Cl ..,B21c 1/00, C22f 1/04 [58] Field of Search 75/138-148; 148/32, 32.5, 2, 11.5 A; 29/193, 193.5, 527.7; 164/76 [56] 2 References Cited UNITED STATES PATENTS 3,160,513 12/1964 Westerveld et al. 117/35 1,579,481 4/1926 Hybinette 75/138 1,916,087 6/1933 Titus 1,932,838 10/1933 Dean et al. 75/147 1,945,297 l/l934 Sterner-Rainer 75/147 FOREIGN PATENTS OR APPLICATIONS 498 ,227 l/l939 Great Britain 1 Apr. 30, 1974 706,721 6/1931 France OTHER PUBLICATIONS Krupotkin et al., The Mechanical Properties of AVOOO Aluminum with Small Additions of Different Elements, Metals Abstract, December, 1969, 31 2291. Krupotkin, Influence of Small Additions of Iron, Nickel and Cobalt on Mechanical Properties and Conductivity of Aluminum, Slavic Library, November 30, 1965, Battell Memorial Institute.

Primary ExaminerRichard 0. Dean Attorney, Agent, or Firml-Ierbert M. Hanegan; Van C. Wilks [57] ABSTRACT Aluminum alloy electrical conductors are produced from aluminum base alloys containing from about 0.55 percent to about 0.95 percent by weight cobalt, optionally up to about 2.0 percent of additional alloying elements, and from about 97.45 percent to about 99.45 percent by weight aluminum. The alloy conductors have an electrical conductivity of at least 57 percent, based on the International Annealed Copper Standard (IACS), and improved properties of increased thermal stability, tensile strength, percent ultimate elongation, ductility, fatigue resistance and yield strength as compared to conventional aluminum alloys of similar electrical properties.

35 Claims, No Drawings ALUMINUM BASE ALLOY ELECTRICAL CONDUCTOR CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of our copending US. Pat. application Ser. No. 54,563, filed July 13, 1970, now abandoned.

The present invention concerns an aluminum base alloy especially suited for producing high strength lightweight electrical conductors including wire, rod and other such articles of manufacture. The present alloy is particularly well suited for use as wire, rod, cable, bus bar, tube connector, terminations, receptacle plugs, or electrical contact devices for conducting electricity.

Aluminum base alloys are finding wider acceptance in the marketplace of today because of their light weight and low cost. One area where aluminum alloys have found increasing acceptance is in the replacement of copper in the manufacture of electrically conductive wire. Conventional electrically conductive aluminum alloy wire (referred to as EC) contains a substantial amount of pure aluminum and trace amounts of impurities such as silicon, vanadium, iron, copper, manganese, magnesium, zinc, boron, and titanium.

Even though desirable in terms of weight and cost, aluminum alloys have received far less than complete acceptance in the electrical conductor marketplace. One of the chief reasons for the lack of complete acceptance is the range of physical properties available with conventional EC aluminum alloy conductors. If the physical properties, such as thermal stability, tensile strength, percentelongation, ductility and yield strength, could be improved significantly without substantially lessening the electrical conductivity of the finished product, a very desirable improvement would be achieved. It is accepted, however, that addition of alloying elements, as in other aluminum alloys, reduces conductivity while improving the physical properties. Consequently, only those additions of elements which improve physical properties without substantially lessening conductivity will yield an acceptable and useful product. i

It is an object of the present invention, therefore, to provide a new aluminum alloy electrical conductor which combines improved physical properties with acceptableelectrical conductivity. These and other objects, features and advantages of the present invention will be apparent from a consideration of the following detailed description of an embodiment of the invention.

In accordance with the present invention, the aluminum base alloy conductor is prepared by mixing cobalt and optionally other alloying elements with aluminum in a furnace to obtain a melt having requisite percentages of elements. It has been found that suitable results are obtained with cobalt present in a weight percentage of about 0.55 percent to about 0.95 percent. Superior results are achieved when cobalt is present in a weight percentage of about 0.60 percent to about 0.90 percent and particularly superior and preferred results are obtained when cobalt is present in a percentage by weight of about 0.65 percent to about 0.85 percent.

The aluminum content of the present alloy may vary from about 97.45 percent to about 99.45 percent by weight with superior results being obtained when the aluminum content varies between about 97.9 percent and 99.40 percent by weight. Particularly superior and preferred results are obtained when the aluminum content is from about 98.15 percent to about 99.35 percent by weight. Since the percentages for maximum and minimum aluminum do not correspond with the total of maximums and minimums for alloying elements, it should be apparent that suitable results are not obtained if the maximum percentages for all alloying elements are employed. If commercial aluminum is employed in preparing the present melt, it is preferred that the aluminum, prior to adding to the melt in the furnace, contain no more 0.1 percent total of trace impurities.

Optionally the present alloy may contain an additional alloying element or group of alloying elements. The total concentration of the optional alloying elements may be up to 2.0 percent by weight; preferably from about 0.1 percent to about 1.5 percent by weight is employed. Particularly superior and preferred results are obtained when 0.1 percent to about 1.0 percent by weight of total additional alloying elements is employed.

Additional alloying elements include the following:

ADDITIONAL ALLOYING ELEMENTS Magnesium Yttrium Vanadium Copper Scandium Rhenium Silicon Thorium Dysprosium Zirconium Tin Terbium Cerium Molybdenum Erbium Niobium Zinc Neodymium Hafnium Tungsten Indium Lanthanum Chromium Boron Tantalum Bismuth Thallium Cesium Antimony Rubidium Titanium Carbon Superior results are obtained with the following additional'alloying elements in the percentages, by weight, as shown:

PREFERRED ADDITIONAL ALLOYING ELEMENTS Magnesium 0.001 to 1.0% Copper OLOS to 1.0% Silicon 0.05 to 1.0% Zirconium 0.01 to 1.0% Niobium 0.0] to 2.0% Tantalum 0.01 to 2.0% Yttrium 0.01 to 1.0% Scandium 0.01 to 1.0% Thorium 0.01 to 1.0% Rare Earth Metals 0.01 to 2.0% Carbon 0.01 to 1.0%

Particularly superior and preferred results are obtained with the use of magnesium as the additional alloying element. Suitable results are obtained with magnesium in a percentage range of about 0.001 to about 1.0 percent by weight with superior results being obtained when about 0.025 percent to about 0.50 percent by weight is used. Particularly superior and preferred results are obtained when about 0.03 percent to about 0.25 percent by weight of magnesium is employed.

The rear earth metals may be present either individually within the percentage range stated or as a partial or total group, the total percentage of the group being within the percentage range stated previously.

It should be understood that the additional alloying elements may be present either individually or as a group of two or more of the elements. It should be understood, however, that if two or more of the additional alloying elements are employed, the total concentration of additional alloying elements should not exceed 2.0 percent by weight.

After preparing the melt, the aluminum alloy is'preferably continuously cast into a continuous bar by a continuous casting machine and then, substantially immediately thereafter, hot-worked in a rolling mill to yield a continuous aluminum alloy rod.

One example of a continuous casting and rolling operation capable of producing continuous rod as specified in this application is contained in the following paragraphs. It should be understood that other methods of preparation may be employed to obtain suitable results but that preferable results are obtained with continuous processing. Such other methods include conventional extrusion and hydrostatic extrusion to obtain rod or wire directly, sintering an aluminum alloy powder to obtain rod or wire directly, casting rod or wire directly from a molten aluminum alloy, and conven-. tional casting of aluminum alloy billets which are subsequently hot-worked to rod and drawn with intermediate anneals into wire.

CONTINUOUS CASTING AND ROLLING OPERATION A continuous casting machine serves as a means for solidifying the molten aluminum alloy metal to provide a cast bar that is conveyed in substantially the condition in which it solidified from the continuous casting machine to the rolling mill, which serves as a means for hot-forming the cast bar into rod or another hotformed product in a manner which imparts substantial movement to the cast bar along a plurality of angularly disposed axes.

The continuous casting machine is of conventional casting wheel type having a casting wheel with a casting groove in its periphery which is partially closed by an endless belt supported by the casting wheel and an idler pulley. The casting wheel and the endless belt cooperate to provide a mold into one end of which molten metal is poured to solidify and from the other end of whichthe cast bar is emitted in substantially that condition in which it solidified.

The rolling mill is of conventional type having a plurality of roll stands arranged to hot-form the cast bar by a series of deformations. The continuous casting machine and the rolling mill are positioned relative to each other so that the cast bar enters the rolling mill substantially immediately after solidification and in substantially that condition in which it solidified. In this condition, the cast bar is at a hot-forming temperature within the range of temperatures for hot-forming the cast bar at the initiation of hot-forming without heating between the casting machine and the rolling mill. In the event that it is desired to closely control the hotforming temperature of the cast bar within the conventional range of hot-forming temperatures, means for adjusting the temperature of the cast bar may be placed between the continuous casting machine and the rolling mill without departing from the inventive concept disclosed herein.

The roll stands each include a plurality of rolls which engage the cast bar. The rolls of each roll stand may be two or more in number and arranged diametrically opposite from one another or arranged at equally spaced positions about the axis of movement of the cast bar through the rolling mill. The rolls of each roll stand of the rolling mill are rotated at a predetermined speed by a power means such as one or more electric motors and the casting wheel is rotated at a speed generally determined by its operating characteristics. The rolling mill serves to hot-form the cast bar into a rod of a crosssectional ara substantially less than that of the cast bar as it enters the rolling mill.

The peripheral surfaces of the rolls of adjacent roll stands in the rolling mill change in configuration; that is, the cast bar is engaged by the rolls of successive roll stands with surfaces of varying configuration, and from different directions. This varying surface engagement of the cast bar in the roll stands functions to knead or shape the metal in the cast bar in such a manner that it it worked at each roll stand and also to simultaneously reduce and change the cross-sectional area of the cast bar into that of the rod.

As each roll stand engages the cast bar, it is desirable that the cast bar be received with sufficient volume per unit of time at the roll stand for the cast bar to generally fill the space defined by the rolls of the roll stand so that the rolls will be effective to work the metal in the cast bar. However, it is also desirable that the space defined by the rolls of each roll stand not be overfilled so that the cast bar will not be forced into the gaps between the rolls. Thus, it is desirable that the rod be fed toward each roll stand at a volume per unit of time which is sufficient to fill, but not overfill, the space defined by the rolls of the roll stand.

As the cast bar is received from the continuous casting machine, it usually has one large flat surface corre sponding to the surface of the endless band and inwardly tapered side surfaces corresponding to the shape of the groove in the casting wheel. As the cast bar is compressed by the rolls of the roll stands, the cast bar is deformed so that it generally takes the crosssectional shape defined by the adjacent peripheries of the rolls of each roll stand.

Thus, it will be understood that with this apparatus, cast aluminum alloy rod of an infinite number of different lengths is prepared by simultaneous casting of the molten aluminum alloy and hot-forming or rolling the cast aluminum bar. The continuous rod has a minimum electrical conductivity of 57 percent IACS and may be used in conducting electricity or it may be drawn to wire of a smaller cross-sectional diameter.

To produce wire of various gauges, the continuous rod produced by the casting and rolling operation is processed in a reduction operation. The unannealed rod (i.e., as rolled to f temper) is cold-drawnthrough a series of progressively constricted dies, without intermediate anneals, to form a continuous wire of desired diameter. It has been found that the elimination of intermediate anneals is preferable during the processing of the rod and improves the physical properties of the wire. Processing with intermediate anneals is acceptable when the requirements for physical properties of the wire permit reduced values. The conductivity of the hard-drawn wire is at least 58 percent IACS. If greater conductivity or increased elongation is desired, the wire may be annealed or partially annealed after the desired wire size is obtained and cooled. Fully annealed wire has a conductivity of at least 59 percent IACS. At

the conclusion of the drawing operation and optional annealing operation, it is found that the alloy wire has the properties of improved tensile strength and yield strength together with improved thermal stability, percient times and at sufficient temperatures to allow complete solubility of the alloying elements withthe base aluminum. An argon atmosphere is provided over the melt to prevent oxidation. Each melt is continuously cent ultimate elongation and increased ductility and fa- 5 cast on a continuous casting machine and immediately tigue resistance as specified previously in this applicahot-rolled through a rolling mill to inch continuous tion. The annealing operation may be continuous as in rod. Wire is then drawn from the rod in both the asresistance annealing, induction annealing, convection rolled condition (hard rod) and after being annealed annealing by continuous furnaces or radiation annealfor 5 hours at 650 F (soft rod). The final wire diameter ing by continuous furnaces, or, preferably, may be 10 obtained is 0.107 inches, 10 gauge AWG. Wire from batch annealed in a batch furnace. When continuously each type rod is tested in both the as-drawn condition annealing, temperatures of about 450 F to about (hard wire) and after being annealed for five hours at l,200 F may be employed with annealing times of 650 F (soft wire). about 5 minutes to about 1/l0,000 of a minute. Gener- The types of alloys employed and the results of the ally, however, continuous annealing temperatures and tests performed thereon are as follows:

TABLE C0 Mg HR SR HW-HR SW-SR SW HR SW-SR Properties .60 3.9 33.2 1.7 2.0 29.2 31.5 Elong.

23,265 13,341 31,249 28,280 14,865 13,000 UTS 62.19 62.43 61.70 62.20 62.83 62.38 IACS .80 4.7 25.0 2.5 2.4 30.1 31.8 Elong.

25,215 15,272 31,886 30,580 16,445 15,090 UTS 60 92 60.66 60.96 61.45 62.0 61.53 lACS .80 .10 3.2 19.4 2.0 2.0 21.5 26.1 Elong.

28,650 16,720 41,200 34,580 18,250 16,390 UTS 59.89 60.32 59.32 59.93 60.99 60.80 lACS HR Hard Rod SR Soft Rod HW-HR Hard Wire drawn from Hard Rod HW-SR Hard W1rc drawn from Soft Rod SW-HR Solt W1rc drawn from Hard Rod SW-SR Sol't Wire drawn from Soft Rod Elong. 11 Percent Ultimate Elongation U'IS Ultimate Tensile Strength IACS Conductivity in Percentage lACS times may be adjusted to meet the requirements of the Soft wire and soft rod are the fully annealed forms of particular overall processing operation so long as the the products. desired physical properties are achieved. in a batch annealing operation, a temperature of approximately EXAMPLE NO. 2 4 F to a ut is em lo (1 with residence b0 F p ya 40 An additional alloy melt is prepared accordmg to Extimes of about 30 minutes to about 24 hours. As menample No. 1 so that the composition is as follows in tioned with respect to continuous annealing, in batch weight percent. annealing the times and temperatures may be varied to suit the overall process so long as the desired physical properties are obtained. Cobalt 0.60% It has been found that the properties of a Number 10 Magftesium 015%,

Aluminum Remamder gauge (American w1re gauge) fully annealed soft w1re of the present alloy vary between the following figures: The melt is processed to a 10 gauge Soft wire from hard rod. The physical properties of the wire are as follows:

Tensile Yield Conductivity Strength, psi. Elongation Strength, psi.

Ultimate Tensile Strength 16,440 psi Percent Ultimate Elongation 21% 59% 63+% 12,000 24,000 12% 30% 8,000 18,000 Conductivity 60.1% AC5 A more complete understanding of the invention will be obtained from the following examples: EXAMPLE 3 An additional alloy melt is prepared according to Ex- EXAMPLE 1 ample No. 1 so that the composition is as follows in Various melts are prepared by adding the required weight percent: amount of alloying elements to 1,816 grams of molten aluminum, containing less than 0.l percent trace ele- C b I O 80% o ment1mpurit1es,to ach eve a percentage concentration Misch Metal 10% of elements as shown in the accompanying table; the Aluminum Remainder remainder being aluminum. Graphite crucibles are used except in those cases where the alloying elements are known carbide formers, in which cases aluminum oxide crucibles are used. The melts are held for suffi- Misch metal is a commercial designation for a blend of rare earth metals and Thorium obtained during the processing of Thorium metal.

The melt is processed to a No. 10 gauge soft wire from hard rod. The physical properties of the wire are as follows:

Ultimate Tensile Strength 18,000 psi Percent Ultimate Elongation Conductivity 59.2% IACS EXAMPLE NO. 4

An additional alloy melt is prepared according to Example No. 1 so that the composition is as follows in weight percent:

Ultimate Tensile Strength l8,600 psi Percent Ultimate Elongation 18.5%

Conductivity 59.3% lACS ADDITIONAL EXAMPLES Additional alloy melts are prepared according to Example No. l. The composition and the physical properties of No. 10 gauge soft wire from hard rod of the alloy melts are as follows:

TABLE ll lACS Example No. Co Mg UTS in psi Elongation Conductivity 5933: 8-283" Through testing and analysis of an alloy containing 0 I 6 Tantalum 018% 0.80 weight percent cobalt and the remainder alum1- Aluminum Remainder num, it has been found that the present aluminum base The melt is processed to a No. 10 gauge soft 'wire from hard rod. The physical properties of the wire are as follows:

Ultimate Tensile Strength 17,900

Percent Ultimate Elongation 20% Conductivity 59.05%

EXAMPLE NO. 5

An additional alloy melt is prepared according to Example No. 1 so that the composition is as follows in weight percent:

Cobalt 0.60% Copper 0. l 5% Silicon 0.20% Aluminum Remainder The melt is processed to a No. 10 gauge soft wire from hard rod. The physical properties of the wire are as follows:

Ultimate Tensile Strength 16,700 Percent Ultimate Elongation 19.5% Conductivity 59.8%

Cobalt 0.80% Zirconium 0.60% Aluminum Remainder alloy after cold working includes an intermetallic compound precipitate. The compound is identified as cobalt aluminate (Co Al This intermetallic compound is found to be very stable and especially so at high temperatures. The compound also has a low tendency to coalesce during annealing of products formed from the alloy and the compound is generally incoherent with the aluminum matrix. The mechanism of strengthening for this alloy is in part due to the dispersion of the intermetallic compound as a precipitate throughout the aluminum matrix. The precipitate tends to pin dislocation sites which are created during cold working of wires formed from the alloy. Upon examination of the intermetallic compound precipitate in a cold drawn wire, it is found that the precipitates are oriented in the direction of drawing. In addition, it is found that the precipitates are rod-like or plate-like in configuration and a majority are less than 2 microns in length and less than micron in width.

Other intermetallic compounds may also be formed depending upon the constituents of the melt and the relative concentrations of the alloying elements. Those intermetallic compounds include the following: MgCoAl, Co Al CeAl CeAl VAl VAI Val VAl WAI Zr Al, Zr Al, LaAl.,, LaAl For the purpose of clarity, the following terminology used in this application is explained as follows:

Aluminum alloy rod product A solid product that is long in relation to its cross-section. Rod normally has a cross-section of between three inches and 0.375 inches.

Aluminum alloy wire product A solid wrought product that is long in relation to its cross-section,

which is square or rectangular with sharp or rounded corners or edges, or is round, a regular hexagon or a regular octagon, and whose diameter or greatest perpendicular distance between parallel faces is between 0.374 inches and 0.0031 inches.

While this invention has been described in detail with particular reference to preferred embodiments thereof, it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described hereinbefore and as defined in the appended claims.

We claim:

I. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent lACS consisting essentially of from about 0.55 to about 0.95 weight percent cobalt, from about 0.001 to about 1.0 weight percent magnesium, the remainder being aluminum with associated trace elements, said aluminum alloy electrical conductor having the following properties when measured as a No. 10 A.W.G. fully annealed wire:

12,000 24,000 psi 12% 30% 8,000 18,000 psi Tensile strength Elongation Yield strength 2. Aluminum alloy electrical conductor of claim 1 wherein magnesium is present in an amount ranging from about 0.025 percent to about 0.50 percent, by weight.

3. Aluminum alloy electrical conductor of claim 1 wherein the weight percentages of the constituents are as follows:

Cobalt 0.60% Magnesium (1.15% Aluminum remainder 4. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent lACS consisting essentially of from about 0.55 to about 0.95 weight per- 12,000 24,000 psi 12% 30% 8,000 18,000 psi Tensile strength Elongation Yield strength I 5. Aluminum alloy electrical conductor according to claim 4 wherein the weight percentages of the constituents are as follows:

Cobalt 0.60% Copper 0.15% Silicon 0.20% Aluminum remainder 6. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent IACS consisting essentially of from about 0.55 to about 0.95 weight per cent cobalt, from about 0.01 to about 1.0 weight percent misch metal, the remainder being aluminum with associated trace elements, said aluminum alloy electrical conductor having the following properties when measured as a No. 10 A.W.G. fully annealed wire:

12,1100 24,000 psi 12% 30% 8,000 18,000 psi Tensile strength Elongation Yield strength 7. Aluminum alloy electrical conductor according to claim 6 wherein the weight percentages of the constituents are as follows:

Cobalt 0.80% Misch metal 1.0% Aluminum remainder .cal conductor having the following properties when measured as a No. 10 A.W.G. fully annealed wire:

12,000 24,000 psi 12% 30% 8,000 18,000 psi Tensile strength Elongation Yield strength 9. Aluminum alloy electrical conductor according to claim 8 wherein the weight percentages of the constituents are as follows:

Cobalt 0.60% Niobium 0.30% Tantalum 0.18% Aluminum remainder 10. Aluminum alloy electrical conductor according to claim 8 wherein the weight percentages of the constituents are as follows:

Cobalt 0.80% Zirconium 0.60% Aluminum remainder a wire.

15. The aluminum alloy electrical conductor of claim 6 wherein said conductor is in the form of a rod.

16. The aluminum alloy electrical conductor according to claim 6 wherein said conductor is in the form of a wire. r

17. The aluminum alloy electrical conductor of claim 8 wherein said conductor is in the form of a rod.

18. The aluminum alloy electrical conductor according to claim 8 wherein said conductor is in the form of a wire.

19. Method of preparing the aluminum alloy conductor of claim 1, comprising the steps of:

A. alloying said named constituents;

B. casting the alloy in a moving mold formed between a groove in the periphery of a rotating casting wheel and a metal belt lying adjacent said groove for a portion of its length; and

C. hot rolling the cast alloy substantially immediately after casting while the cast alloy is in substantially that condition as cast to form a continuous rod. 20. Method of preparing the aluminum alloy conductor in accordance with claim 19 including the further step of drawing said conductor to form wire, without carrying out any annealing step.

21. The method according to claim 19 wherein the alloying step also includes the addition of magnesium in an amount sufficient to yield an alloy having the following weight percentages:

Cobalt 0.60% Magnesium 0.15% Aluminum remainder 22. Method of preparing the aluminum alloy conductor of claim 4, comprising the steps of:

A. alloying said named constituents; B. casting the alloy in a moving mold formed between a groove in the periphery of a rotating casting wheel and a metal belt lying adjacent said groove for a portion of its length; and C. hot rolling the cast alloy substantially immediately after casting while the cast alloy is in substantially that condition as cast to form a continuous rod. 23. Method of preparing the aluminum alloy conductor in accordance with claim 22 including the further step of drawing said conductor to form wire, without carrying out any annealing step.

24. Method of preparing the aluminum alloy conduc- I tor of claim 6, comprising the steps of:

A. alloying said named constituents; B. casting the alloy in a moving mold formed between a groove in the periphery of a rotating casting wheel and a metal belt lying adjacent said groove for a portion of its length; and C. hot rolling the cast alloy substantially immediately after casting while the cast alloy-is in substantially that condition as cast to form a continuous rod. 25. Method of preparing the aluminum alloy conductor in accordance with claim 24 including the further step of drawing said conductor to form wire, without carrying out any annealing step.

26. Method of preparing the aluminum alloy conductor of claim 8, comprising the steps of:

A. alloying said named constituents; B. casting the alloy in a moving mold formed between a groove in the periphery of a rotating casting wheel and a metal belt lying adjacent said groove for a portion of its length; and C. hot rolling the cast alloy substantially immediately after casting while the cast alloy is in substantially that condition as cast to form a continuous rod. 27. Method of preparing the aluminum alloy conductor in accordance with claim 26 including the further step of drawing said conductor to form wire, without carrying out any annealing step.

28. The method according to claim 22 wherein the alloying step also includes the addition of copper and silicon in an amount sufficient to yield an alloy having the following weight percentages:

Cobalt 0.60% Copper 0.15% Silicon 0.20% Aluminum remainder 29. The method according to claim 24 wherein the alloying step also includes the addition of misch metal in an amount sufficient to yield an alloy having the following weight percentages:

Cobalt 0.80% Miseh metal 1.0% Aluminum remainder 30. The method according to claim 26 wherein the alloying step also includes the addition of niobium and tantalum in an amount sufficient to yield an alloy having the following weight percentages:

Cobalt 0.60% Niobium 0.30% Tantalum 0.18% Aluminum remainder 31. The method according to claim 26 wherein the alloying step also includes the addition of zirconium in an amount sufficient to yield an alloy having the following weight percentages:

Cobalt 0.80% Zirconium 0.60% Aluminum remainder 32. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent lACS consisting essentially of from about 0.55 to about 0.95 weight percent cobalt, from about 0.001 to about 1.0 weight percent magnesium, the remainder being aluminum with associated trace elements, said aluminum alloy electrical conductor having the following properties when measured as a fully annealed wire:

Tensile strength Yield strength at least 12,000 psi at least 8,000 psi Tensile strength Yield strength at least 12,000 psi at least 8,000 psi 34. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent IACS consisting essentially of from about 0.55 to about 0.95 weight percent cobalt, from about 0.01 to about 1.0 weight percent misch metal, the remainder being aluminum with associated trace elements, said aluminum alloy electrical conductor having the following properties when measured as a fully annealed wire:

at least l2,000 psi Tensile strength at least 8,000 psi Yield strength 35. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent IACS consisting essentially of from about 0.55 to about 0.95 weight percent cobalt, from about 0.01 to about 1.0 weight of an at least 12,000 psi Tensile strength at least 8,000 psi Yield strength 

2. Aluminum alloy electrical conductor of claim 1 wherein magnesium is present in an amount ranging from about 0.025 percent to about 0.50 percent, by weight.
 3. Aluminum alloy electrical conductor of claim 1 wherein the weight percentages of the constituents are as follows:
 4. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent IACS consisting essentially of from about 0.55 to about 0.95 weight percent cobalt, from about 0.05 to about 1.0 weight percent of an additional alloying element taken from the group consisting of copper, silicon, and mixtures thereof, the remainder being aluminum with associated trace elements, said aluminum alloy electrical conductor having the following properties when measured as a No. 10 A.W.G. fully annealed wire:
 5. Aluminum alloy electrical conductor according to claim 4 wherein the weight percentages of the constituents are as follows:
 6. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent IACS consisting essentially of from about 0.55 to about 0.95 weight percent cobalt, from about 0.01 to about 1.0 weight percent misch metal, the remainder being aluminum with associated trace elements, said aluminum alloy electrical conductor having the following properties when measured as a No. 10 A.W.G. fully annealed wire:
 7. Aluminum alloy electrical conductor according to claim 6 wherein the weight percentages of the constituents are as follows:
 8. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent IACS consisting essentially of from about 0.55 to about 0.95 weight percent cobalt, from about 0.01 to about 1.0 weight percent of an additional alloying element taken from the group consisting of niobium, tantalum, zirconium, and mixtures thereof, the remainder being aluminum with associated trace elements, said aluminum alloy electrical conductor having the following properties when measured as a No. 10 A.W.G. fully annealed wire:
 9. Aluminum alloy electrical conductor according to claim 8 wherein the weight percentages of the constituents are as follows:
 10. Aluminum alloy electrical conductor according to claim 8 wherein the weight percentages of the constituents are as follows:
 11. The aluminum alloy electrical conductor of claim 1 wherein said conductor is in the form of a rod.
 12. The aluminum alloy electrical conductor according to claim 1 wherein said conductor is in the form of a wire.
 13. The aluminum alloy electrical conductor of claim 4 wherein said conductor is in the form of a rod.
 14. The aluminum alloy electrical conductor according to claim 4 wherein said conductor is in the form of a wire.
 15. The aluminum alloy electrical conductor of claim 6 wherein said conductor is in the form of a rod.
 16. The aluminum alloy electrical conductor according to claim 6 wherein said conductor is in the form of a wire.
 17. The aluminum alloy electrical conductor of claim 8 wherein said conductor is in the form of a rod.
 18. The aluminum alloy electrical conductor according to claim 8 wherein said conductor is in the form of a wire.
 19. Method of preparing the aluminum alloy conductor of claim 1, comprising the steps of: A. alloying said named constituents; B. casting the alloy in a moving mold formed between a groove in the periphery of a rotating casting wheel and a metal belt lying adjacent said groove for a portion of its length; and C. hot rolling the cast alloy substantially immediately after casting while the cast alloy is in substantially that condition as cast to form a continuous rod.
 20. Method of preparing the aluminum alloy conductor in accordance with claim 19 including the further step of drawing said conductor to form wire, without carrying out any annealing step.
 21. The method according to claim 19 wherein the alloying step also includes the addition of magnesium in an amount sufficient to yield an alloy having the following weight percentages:
 22. Method of preparing the aluminum alloy conductor of claim 4, comprising the steps of: A. alloying said named constituents; B. casting thE alloy in a moving mold formed between a groove in the periphery of a rotating casting wheel and a metal belt lying adjacent said groove for a portion of its length; and C. hot rolling the cast alloy substantially immediately after casting while the cast alloy is in substantially that condition as cast to form a continuous rod.
 23. Method of preparing the aluminum alloy conductor in accordance with claim 22 including the further step of drawing said conductor to form wire, without carrying out any annealing step.
 24. Method of preparing the aluminum alloy conductor of claim 6, comprising the steps of: A. alloying said named constituents; B. casting the alloy in a moving mold formed between a groove in the periphery of a rotating casting wheel and a metal belt lying adjacent said groove for a portion of its length; and C. hot rolling the cast alloy substantially immediately after casting while the cast alloy is in substantially that condition as cast to form a continuous rod.
 25. Method of preparing the aluminum alloy conductor in accordance with claim 24 including the further step of drawing said conductor to form wire, without carrying out any annealing step.
 26. Method of preparing the aluminum alloy conductor of claim 8, comprising the steps of: A. alloying said named constituents; B. casting the alloy in a moving mold formed between a groove in the periphery of a rotating casting wheel and a metal belt lying adjacent said groove for a portion of its length; and C. hot rolling the cast alloy substantially immediately after casting while the cast alloy is in substantially that condition as cast to form a continuous rod.
 27. Method of preparing the aluminum alloy conductor in accordance with claim 26 including the further step of drawing said conductor to form wire, without carrying out any annealing step.
 28. The method according to claim 22 wherein the alloying step also includes the addition of copper and silicon in an amount sufficient to yield an alloy having the following weight percentages:
 29. The method according to claim 24 wherein the alloying step also includes the addition of misch metal in an amount sufficient to yield an alloy having the following weight percentages:
 30. The method according to claim 26 wherein the alloying step also includes the addition of niobium and tantalum in an amount sufficient to yield an alloy having the following weight percentages:
 31. The method according to claim 26 wherein the alloying step also includes the addition of zirconium in an amount sufficient to yield an alloy having the following weight percentages:
 32. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent IACS consisting essentially of from about 0.55 to about 0.95 weight percent cobalt, from about 0.001 to about 1.0 weight percent magnesium, the remainder being aluminum with associated trace elements, said aluminum alloy electrical conductor having the following properties when measured as a fully annealed wire:
 33. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent IACS consisting essentially of from about 0.55 to about 0.95 weight percent cobalt, from about 0.05 to about 1.0 weight percent of an additional alloy element taken from the group consisting of copper, silicon, and mixtures thereof, the remainder being aluminum with associated trace elemEnts, said aluminum alloy electrical conductor having the following properties when measured as a fully annealed wire:
 34. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent IACS consisting essentially of from about 0.55 to about 0.95 weight percent cobalt, from about 0.01 to about 1.0 weight percent misch metal, the remainder being aluminum with associated trace elements, said aluminum alloy electrical conductor having the following properties when measured as a fully annealed wire:
 35. Aluminum alloy electrical conductor having a minimum conductivity of 57 percent IACS consisting essentially of from about 0.55 to about 0.95 weight percent cobalt, from about 0.01 to about 1.0 weight of an additional alloying element taken from the group consisting of niobium, tantalum, zirconium, and mixtures thereof, the remainder being aluminum with associated trace elements, said aluminum alloy electrical conductor having the following properties when measured as a fully annealed wire: 